1. Field of the Invention
The present invention relates to image processing apparatuses and image processing methods. More specifically, the present invention relates to an image processing apparatus and an image processing method configured to optimally transfer data in response to a transfer capability of a network.
2. Description of the Related Art
Conventionally, there are systems that transfer read data that are read from image processing apparatuses such as a digital copying machine, a facsimile machine, and an image scanner to another apparatus through a network such as a data bus. In such systems, optimizing a processing speed as a whole system is needed because a waiting time may occur until the systems transfer the read data to the apparatus for outputting, especially if a transferring speed of the network is slow.
Under the above mentioned conditions, for example, in a case of multifunction products in middle and low speed tiers, there are demands for cost reduction and improvement of readout productivity. On the other hand, if a low-cost controller of 32-bit bus is adopted for the multifunction products in the low or middle speed tiers for the cost reduction, data transfer capability to transfer the read data decreases. Moreover, if a reading line speed is increased and a reading cycle of a line is shortened, a margin of the data transfer capability decreases.
Here, if the multifunction products have enough data transfer capability proportional to the reading line speed, the above-mentioned problems do not occur. However, for example, under reading conditions of “an automatic color determination in 600 dpi resolution for A4 (which is a paper size of Japanese Industrial Standards) manuscript” or “a color Clear Write PDF (which is a type that divides a background photograph part and a foreground letter part, and compresses the parts by performing image processing suitable for each of the features; PDF stands for Portable Document Format) in 600 dpi resolution for A4 manuscript”, an amount of the read data may exceed the data transfer capability. Furthermore, in order to meet these conditions, adopting a controller of a 64-bit bus that can transfer data at high speed causes a significant increase in cost.
Therefore, in a readout apparatus that performs readout under a readout condition beyond the transfer capability for a data amount to be transferred, a speed reduction control technique is known where it is determined whether the data amount is within the transfer capability before the readout, and the data transfer can be carried out by slowing the readout speed if the data transfer is impossible.
In addition, for example, as a unit that adjusts speeds of the apparatuses of the readout apparatus and an output device by considering a data transfer processing capability of the network, a control unit that controls a reading speed (i.e., mechanical variable magnification) of the readout apparatus and magnification change processing is described in Japanese Laid-open Patent Application Publication No. 2006-165698 (which is hereinafter called Patent Document 1).
Here, in Patent Document 1, availability of deceleration control is determined based on a data transfer size (i.e., amount). However, for example, there is a case where a size of set manuscripts to be read as data varies from manuscript to manuscript. In this case, adjusting the data transfer amount according to the manuscript size allows for optimal data transfer. To do this, however, because gaining the manuscript size before reading the manuscript is needed, it is impossible to preliminarily gain the manuscript size at a detection timing such as an automatic size detection, and to perform the deceleration control that adjusts the data transfer amount according to the manuscript size.
Moreover, since the deceleration control conditions vary according to data transfer circumstances, a magnification changing form varies according to the data amount of the data transfer through a network even if the same manuscript is read at the same resolution, by which every output image cannot have a same image quality.